package com.baosight.risk.common.utils;

import java.io.UnsupportedEncodingException;
import java.security.MessageDigest;
import java.security.NoSuchAlgorithmException;
import java.security.SecureRandom;
import javax.crypto.Cipher;
import javax.crypto.SecretKey;
import javax.crypto.SecretKeyFactory;
import javax.crypto.spec.DESKeySpec;


public class EncryptUtil {
    private static MessageDigest digest = null;

    private final static String CHAR = "0123456789abcdefghijklmnopqrstuvwxyzABCDEFGHIJKLMNOPQRSTUVWXYZ!@#$%^&*?.,;:<>[]{}|";

    /**
     * 生成加密密码中的盐
     *
     * @return 返回包涵32个字符的字符串（数字、字母、特殊符号）
     */
    public static String generateSalt() {
        int length = CHAR.length();
        String s = "";
        for (int i = 0; i < 32; i++) {
            int m = (int) (Math.random() * length);
            s += CHAR.charAt(m);
        }
        return s;
    }


    public static final String MD5Encode(String password) {
        if (digest == null) {
            try {
                digest = MessageDigest.getInstance("MD5");
            } catch (NoSuchAlgorithmException nsae) {
                nsae.getStackTrace();
            }
        }
        try {
            digest.update(password.getBytes("utf-8"));
        } catch (UnsupportedEncodingException e) {
            e.getStackTrace();
        }
        return encodeHex(digest.digest());

    }

    private static final String encodeHex(byte bytes[]) {
        StringBuffer buf = new StringBuffer(bytes.length * 2);
        for (int i = 0; i < bytes.length; i++) {
            if ((bytes[i] & 0xff) < 16)
                buf.append("0");
            buf.append(Long.toString(bytes[i] & 0xff, 16));
        }

        return buf.toString();
    }

    private static final String PASSWORD_CRYPT_KEY = "__jDlog_";
    private final static String DES = "DES";

    /**
     * 加密
     *
     * @param src 数据源
     * @param key 密钥，长度必须是8的倍数
     * @return 返回加密后的数据
     * @throws Exception
     */
    public static byte[] encrypt(byte[] src, byte[] key) throws Exception {

        // DES算法要求有一个可信任的随机数源

        SecureRandom sr = new SecureRandom();

        // 从原始密匙数据创建DESKeySpec对象

        DESKeySpec dks = new DESKeySpec(key);

        // 创建一个密匙工厂，然后用它把DESKeySpec转换成

        // 一个SecretKey对象

        SecretKeyFactory keyFactory = SecretKeyFactory.getInstance(DES);

        SecretKey securekey = keyFactory.generateSecret(dks);

        // Cipher对象实际完成加密操作

        Cipher cipher = Cipher.getInstance(DES);

        // 用密匙初始化Cipher对象

        cipher.init(Cipher.ENCRYPT_MODE, securekey, sr);

        // 现在，获取数据并加密

        // 正式执行加密操作

        return cipher.doFinal(src);

    }

    /**
     * 解密
     *
     * @param src 数据源
     * @param key 密钥，长度必须是8的倍数
     * @return 返回解密后的原始数据
     * @throws Exception
     */

    public static byte[] decrypt(byte[] src, byte[] key) throws Exception {

        // DES算法要求有一个可信任的随机数源

        SecureRandom sr = new SecureRandom();

        // 从原始密匙数据创建一个DESKeySpec对象

        DESKeySpec dks = new DESKeySpec(key);

        // 创建一个密匙工厂，然后用它把DESKeySpec对象转换成

        // 一个SecretKey对象

        SecretKeyFactory keyFactory = SecretKeyFactory.getInstance(DES);

        SecretKey securekey = keyFactory.generateSecret(dks);

        // Cipher对象实际完成解密操作

        Cipher cipher = Cipher.getInstance(DES);

        // 用密匙初始化Cipher对象

        cipher.init(Cipher.DECRYPT_MODE, securekey, sr);

        // 现在，获取数据并解密

        // 正式执行解密操作

        return cipher.doFinal(src);

    }

    /**
     * 密码解密
     *
     * @param data
     * @return
     * @throws Exception
     */

    public final static String decrypt(String data) {

        try {

            return new String(decrypt(hex2byte(data.getBytes()),

                    PASSWORD_CRYPT_KEY.getBytes()));

        } catch (Exception e) {

        }

        return null;

    }

    /**
     * 密码加密
     *
     * @param password
     * @return
     * @throws Exception
     */

    public final static String encrypt(String password) {

        try {

            return byte2hex(encrypt(password.getBytes(),
                    PASSWORD_CRYPT_KEY.getBytes()));
        } catch (Exception e) {

        }

        return null;

    }

    /**
     * 二行制转字符串
     *
     * @param b
     * @return
     */

    public static String byte2hex(byte[] b) {

        String hs = "";

        String stmp = "";

        for (int n = 0; n < b.length; n++) {

            stmp = (Integer.toHexString(b[n] & 0XFF));

            if (stmp.length() == 1)

                hs = hs + "0" + stmp;

            else

                hs = hs + stmp;

        }

        return hs.toUpperCase();

    }

    public static byte[] hex2byte(byte[] b) {

        if ((b.length % 2) != 0)
            throw new IllegalArgumentException("长度不是偶数");

        byte[] b2 = new byte[b.length / 2];

        for (int n = 0; n < b.length; n += 2) {

            String item = new String(b, n, 2);

            b2[n / 2] = (byte) Integer.parseInt(item, 16);

        }

        return b2;
    }

    public static void main(String[] args) {
//		System.out.println(codedPassword("d81815password"));
        System.out.println(encrypt("admin123"));
        System.out.println(decrypt("ACEB1D8E96AB2739"));


    }

}
